19
FIGURE 41 -
INSTALLING PRESSURE RELIEF SPRING SEAT
PRESSURE RELIEF & BYPASS VALVE
DISASSEMBLY
28. If the steering gear is equipped with a pressure relief
valve, begin disassembly by removing the plug (42) and
its sealing washer (44) from the valve body (7).
Figure
40.
29. Remove the spring (43), spring seat (45), adjusting shims
(41) and the valve piston (46).
Figure 40.
30. Using a wide bladed screwdriver or tool 298077, remove
the valve seat (48) and its sealing washer (47). If the
gear is so equipped, remove the bypass valve spring
(51) and the ball (52).
SPINDLE DISASSEMBLY
CAUTION: Do not attempt disassembly of the spindle
assembly which contains the rotary valve. Individual
replacement parts are NOT available. It must be treated
as a single component.
CLEANING AND INSPECTION
CLEANING
Wash all parts individually in clean solvent and dry thoroughly.
All non-metallic parts should be discarded and replaced with
new.
INSPECTION
Parts found broken, cracked, distorted, excessively pitted,
or scored must be replaced. Cause for the replacement of
any part should be investigated and corrected to prevent
reoccurrence.
Visually inspect all parts carefully paying particular attention
to:
1. Bearings and bearing surfaces should not exhibit
brinelling, pitting, spalling or cracks. If, upon inspection,
it is determined that the outer races of the roller bearings
(26) contained in the housing (22) or the side cover (31)
are not serviceable, the entire housing or side cover must
be replaced. If the outer ball bearing race (8) remaining
in the valve body (7) is not serviceable, the entire valve
body must be replaced. Inspect the bearing surfaces of
both the inputs.
2. Gear teeth in the output shaft and piston may show
signs of polishing and slight wear; however, pitting,
spalling, and cracks should not be present.
3. Output and input shaft splines.
4. Check the ball rolling surfaces on the exterior of spindle
and interior of piston for cracks, pitting, spalling and
brinelling.
5. Exterior of piston and interior of housing bore.
Note:
Minor scuffing of the piston exterior and housing
bore can be considered normal. If deep scoring is
detected, the affected parts should be replaced as
leakage will occur and steering control and reaction
will be affected. Do not attempt honing or boring of
these parts as leakage rates will increase.
6. Pitman arm.
7. Exterior of housing and its mounting lugs.
8. Valve body and porting.
REASSEMBLY OF THE POWER STEERING
GEAR
GENERAL
To ensure proper operation of the power steering gear, the
following procedure and its sequence should be carefully
followed. Failure to do so may result in damage to the gear
or faulty operation or both.
The appropriate maintenance kits should be obtained prior
to reassembly.
VALVE BODY & SPINDLE REASSEMBLY
1. If the power steering gear is so equipped, install the
bypass valve ball (52) and spring (51) in the valve body
(7).
Figure 40.
2. Install the sealing washer (47) around the pressure relief
valve seat (48) and using a large bladed screwdriver or
tool piece number 298077, install both in the valve
body(7). Tighten the valve seat to between 15 and 18
pound feet.
Figure
40
.
3. Install the pressure relief valve piston (46), spring seat
(45), and spring (43) in the valve body.
Figure 41.
CAUTION: The spring seat (45) must be installed as
illustrated in
Figure 40
. Incorrect installation of the spring
